#define _CRT_SECURE_NO_WARNINGS 1
#include"9.24.h"

int GetMonthDay(int year, int month)
{
	assert(month > 0 && month < 13);
	static int days[13] = {0,31,28,31,30,31,30,31,31,30,31,30,31 };
	if (month == 2 && ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)))
	{
		return 29;
	}
	return days[month];
}
Date::Date(int year = 1900, int month = 1, int day = 1)
{
	_year = year;
	_month = month;
	_day = day;
}

Date::Date(const Date& d)
{
	this->_year = d._year;
	this->_month = d._month;
	this->_day = d._day;
}
		
Date& Date::operator=(const Date& d) {
	
	this->_year = d._year;
	this->_month = d._month;
	this->_day = d._day;
	return *this;
}

Date:: ~Date() 
{

}
Date& Date:: operator+=(int day)
{
	_day += day;
	while (_day > GetMonthDay(_year,_day))
	{
		_day -= GetMonthDay(_year, _month);
		_month++;
		if (_month == 13)
		{
			_year++;
			_month = 1;
		}
	}
	return *this;
}
Date Date:: operator+(int day)

{
	Date tmp(*this);
	tmp += day;
	return tmp;
}
Date& Date::operator-=(int day)
{
	_day -= day;
	while (_day <= 0)
	{
		--_month;
		
		if (_month == 0)
		{
			_year--;
			_month == 12;
		}
		_day += GetMonthDay(_year, _month);
	}
	return *this;
}
Date Date::operator-(int day)
{
	Date tmp = *this;
	tmp -= day;
	return tmp;
}

Date& Date:: operator++()
{
	*this += 1;
	return *this;
}

Date Date:: operator++(int)
{
	Date tmp = *this;
	*this += 1;
	return tmp;
}

Date Date::operator--(int)
{
	Date tmp = *this;
	*this -= 1;
	return tmp;

}

Date& Date:: operator--()
{
	
		*this -= 1;
		return *this;
}

bool Date:: operator>(const Date& d)
{
	if (_year > d._year)
	{
		return true;
	}
	else if (_year == d._year)
	{
		if (_month > d._month)
		{
			return true;
		}
		else(_month == d._month);
		{
			if (_day > d._day)
			{
				return true;
			}
		}
    }
	return false;
}

bool Date::operator==(const Date& d)
{
	return _year == d._year && _month == d._month && _day == d._day;
}

bool Date::operator >= (const Date& d)
{
	return *this > d || *this == d;
}

bool Date::operator < (const Date& d)
{
	return !(*this >= d);
}

bool Date::operator <= (const Date& d)
{
	return !(*this > d);
}

bool Date::operator != (const Date& d)
{
	return !(*this == d);
}

int Date::operator-(const Date& d)
{
	Date max = *this;
	Date min = d;
	int flag = 1;
	if (*this < d)
	{
		max = d;
		min = *this;
	}
	int n = 0;
	while (max != min)
	{
		n++;
		min++;
	}
	return n;
}